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International Baccalaureate: Biology
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The pathogen avoidance model states that females select for males with secondary s*x traits in order to distinguish between the diseased and the healthy males in order to stay safe from pathogens. Both theories are widely used to explain many evolutionary trends, but are they mutually exclusive? It is possible that both theories are correct in certain scenarios. However, one must look into the mechanisms of both in order to find out. Overview of Sexy Sons Hypothesis The sexy son hypothesis which was popularized by Ronald Fisher is currently stated as a possible explanation for the great diversity of ornamental traits in animals.
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How does changing the percentage of sucrose added to yeast affect the rate of respiration of yeast as measured by the height of gas bubbles (froth) ?
produced by the yeast above the yeast-sucrose suspension in 360 seconds. Percentage of sucrose added to the yeast (%) Rate of respiration of yeast as measured by the rate of gas bubbles (froth) produced by the yeast above the yeast-sucrose suspension in 360 seconds (mm/s) Trials 1 2 3 4 5 6 0 0 0 0 0 0 - 5 0.044 0.067 0.11 0.044 0.047 - 10 0.056 0.058 0.067 0.053 0.050 - 15 0.056 0.047 0.053 0.050 0.056 - 20 0.047 0.0083 0.047 0.039 0.044 0.044 Key Colour used to indicate the example calculation of rate Colour used to
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The largest chromosome of the 23 is labeled as chromosome 1. This chromosome, along with the rest, has arms. On the long arm of chromosome 1, we find a code. This code contains 120 letters of the 4 genomes: A, C, G, and T written in a paragraph to from a single gene. The thing that makes this gene so special is that it is constantly being duplicated into what is referred to as RNA. Then, RNA translates DNA into proteins.
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Examine the correlation between soil moisture at different heights up the slope and the length of the longest leaf of a Bracken Fern
Therefore, as soil moisture decreases up the slope, the Bracken Fern up the slope will be progressively smaller as there is less water available in the soil for growth, thus resulting with the largest Bracken Fern consisting at the bottom of the slope. Due to this, I therefore predict that the length of the longest leaf would decrease up the slope as the Bracken Fern get smaller, because if the plant is smaller, its leaves should also reduce in length.
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Sleep is a normal part of human life. Investigate the neurobiological basis of normal healthy sleep and sleep-deprivation.
and rapid eye movement (REM) sleep. NREM sleep if further divided into progressively deeper stages of sleep: stage N1, stage N2, and stage N3 (deep or delta-wave sleep). As NREM stages progress, stronger stimuli are required to result in an awakening. Stage R sleep (REM sleep) has tonic and phasic components. The phasic component is a sympathetically driven state characterized by rapid eye movements (rolling eyes, opening and closing), muscle twitches, and respiratory variability. Tonic REM is a parasympathetically driven state with no eye movements.
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What is the effect of pH levels on the net production, given by the change in dissolved oxygen, in Chlorella pyrenoidosa?
In this experiment, the effects of pH on the net production, from change in dissolved oxygen, were studied. Question: What is the effect of pH levels on the net production, given by the change in dissolved oxygen, in Chlorella pyrenoidosa? Hypothesis: If the test bottles (150 mL containers) are filled with about 20 mL of cultured Chlorella pyrenoidosa sample and 130 mL of pH solutions from pH 6, 7, 8, 9, and 10, and the test bottles are exposed to conditions suitable for survival of Chlorella pyrenoidosa , then the test bottles that contain the optimum pH, that is the
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